Health Info

Traffic Fumes Speed Up Artery Hardening
Where we live has been linked to heart disease risk

(HealthDay News) -- "Location, location, location" has special meaning for people trying to sell a house. But the location of people's homes might have implications for the health of their hearts as well.

The closer people live to heavy traffic, it seems, the greater the risk of heart troubles. Researchers have found that regular exposure to traffic fumes makes people more likely to develop hardening of the arteries, which increases the risk of heart attack.

A German study of 4,500 adults looked at how far they lived from heavy traffic and assessed them for such cardiovascular disease risk factors as diabetes and smoking. A technology called electron-beam automated tomography was then used to measure the degree of participants' vessel calcification -- the buildup of calcium deposits that cause arteries to harden and increase the risk of blockages.

The amount of calcification was directly related to how close participants lived to heavy traffic. Compared with those who lived more than 200 meters (642 feet) from heavy traffic, calcification was 63 percent higher for those who lived less than 50 meters (160 feet) from heavy traffic, 34 percent higher for those who were 51 to 100 meters (164 to 328 feet) away, and 8 percent higher for people who were 100 to 200 meters (328 to 642 feet) away, the study found.

"It's not limited to freeways. We see [artery damage] in inner-city dwellings on heavily traveled streets as well," lead researcher Barbara Hoffmann, head of the unit of environmental epidemiology at the University of Duisburg-Essen , told HealthDay .

The damage seen in people who live close to heavy traffic is similar to that produced by inhaling second-hand smoke, she said, "although the effect we see here in this study is even larger than that caused by second-hand smoke."

It's believed that high levels of particulate pollutants in vehicle exhaust fumes cause most of the blood vessel damage, although there may be other contributing factors, such as constant traffic noise, "which can contribute to high blood pressure," Hoffmann said.

For people who live near heavily traveled roadways, the only immediate protective action they can take is to reduce known cardiac risk factors, such as obesity and high blood pressure, she said. But over the long term, she urged community action to reduce the health risk posed by heavy traffic.

For example, she said, "when they build roads, communities should consider the location of residential buildings and schools."

Participants in the study, published in the journal Circulation , continue to be followed to learn whether the traffic-related artery damage progresses and whether it's associated with a higher incidence of heart attack and other cardiovascular problems.

"The follow-up data will be important to have," Dr. Sidney Smith, professor of medicine at the University of North Carolina and a former president of the American Heart Association, told HealthDay .

He noted that the study was "incomplete because it just looks at calcification" but that the follow-up would look at the incidence of cardiovascular events.

Smith was a member of a committee of experts created by the Heart Association in 2004 to review the literature on air pollution and cardiovascular disease. One of the recommendations made by the committee was that people at high risk for cardiovascular disease limit outdoor activities when air pollution levels are high.

"There is increased concern about environmental pollutants worldwide, and I don't think we should neglect opportunities to reduce this as a global risk factor," Smith said. "Communities need to look at how to reduce ambient pollution levels."

On the Web

To learn more about air pollution and health, visit the American Academy of Family Physicians.

SOURCES: HealthDay News ; Barbara Hoffmann, M.P.H., head of environmental epidemiology, University of Duisburg-Essen, Germany; Sidney Smith, M.D., professor of medicine, University of North Carolina, Chapel Hill, N.C.; July 17, 2007, Circulation
Author: Robert Preidt
Publication Date: July 31, 2008
Copyright © 2008 ScoutNews, LLC. All rights reserved.